Question

What concentration measure changes with temperature?

Answer 1

A solution is the component which contains two parts, solute and solvent. Solute is the substance which gets dissolved, whereas the solvent is the substance which is dissolving medium. The concentration of solution is the amount of solute dissolved in solution.

Complete answer:
The concentration of solutions measure changes with temperature are as follows:
Volume percentage $\left( {\dfrac{V}{V}} \right)$ :
The volume percent is the fraction of the volume of solute to the volume of solution. It is used to represent the concentration of solution when volume of solute is given.
$Volume\;percentage = \dfrac{{volume\;of\;solute}}{{volume\;of\;solution}} \times 100\%$
It depends upon temperature as we know volume is a temperature dependent quantity. It changes by changing the temperature. Hence volume percentage is temperature dependent.
Mass by volume percentage$\left( {\dfrac{w}{v}} \right)$ :
The mass by volume percent is the mass of solute in grams present in one litre of solution. The formula of mass by volume percentage is:
$Mass\;by\;volume = \dfrac{{weight\;of\;solute\;in\;gm}}{{volume\;of\;solution\;in\;l}} \times 100\%$
Again as we can see it contains volume so it changes on changing the temperature. Thus it varies with respect to temperature.
Molarity$(M)$ :
The molarity $(M)$ of the solution is to represent the amount of solute in mole present in the one litre of the solution. The formula of molarity is:
$Molarity = \dfrac{{moles\;of\;solute}}{{volume\;of\;solution\;in\;l}}$
It depends upon temperature because the solution expands or contracts with change in temperature so the molarity of the solution is specific at a given temperature. E.g. $0.1\;M\;HCl$ means solution containing $0.1$ mole of $HCl$ per litre.
Normality$\left( N \right)$ :
The normality $\left( N \right)$ of a solution is defined as the gram equivalent weight of the solute present in one litre of solution. The formula of normality is:
$Normality = \dfrac{{Weight\;of\;solute}}{{Equivalent\;weight\;of\;solute \times volume\;of\;the\;solution}}$
As we know that volume depends upon temperature, i.e. $[V \propto T\;given\;by\;Charles\;law]$ .
Since normality varies with respect to volume, it also changes with respect to temperature.

Note:
Remember that concentration measures like mass percentage, part per million, mole fraction and molality do not depend upon temperature. This is because they are independent of volume as by Charles law $V \propto T$ .